Lexan* Thermoclear* Multiwall SheetLexan* Thermoclear* Multiwall SheetFor Commercial GreenhousesFor Commercial Greenhouses
Specialty Film & Sheet Specialty Film & Sheet -- Building & Construction SegmentBuilding & Construction Segment
2
Content• General Product Overview
• Product Mechanical Properties
• Mechanical Properties vs. Temperature
• Impact Strength
• Hail Simulation
• Light Transmission
• UV Protection
• Weathering test
• Thermal Properties
• Solar Properties
• Dripgard/EasyClean Grades/Softlite
• 10 year Limited Warranty
3
Lexan Thermoclear sheet is an impact resistant, energy saving,
multi-wall polycarbonate glazing.
It features a proprietary surface treatment which provides almost
total resistance against degradation caused by UV radiation in
sunlight.
The entire Lexan* Thermoclear* sheet range carries a minimum
Ten Year Limited Warranty against:
• discoloration
• loss of light transmission
• loss of strength due to weathering
Typical applications include:
• Industrial Roofs and Sidewalls
• Commercial Greenhouses
• Sunroom, Swimming Pool and Conservatory Roofing
• Shopping Center Roofing
• Railway/Metro/Bus Station Roofing
• Sport Stadium Roofing
Lexan* Thermoclear* Multiwall Sheet
4
Why Lexan* Thermoclear* Sheet?
5
Why Lexan* Thermoclear* Sheet?Broad Portfolio
169X Structure
6
Why Lexan* Thermoclear* Sheet?UV Protection
Sample 1 - ΔΔΔΔ Yi = 0
Sample 2 - ΔΔΔΔ Yi = 2 - Lexan Thermoclear Plus sheet warranty
Sample 1 - ΔΔΔΔ Yi = 0
Lexan* Thermoclear* Plus sheet has on two sides proprietary UV-protected
surface, giving superior resistance to outdoor weathering.
Lexan Thermoclear offers a ten year limited written warranty against
discoloration, loss of light transmission and loss of impact strength
due to weathering.
The photos presented here show 3 polycarbonate multiwall sheet samples
displaying 3 levels of Yellowness Index
Sample 1: Yellowness Index of 0 Δ
(Reference sample = original value)
Sample 2: Yellowness Index of 2 Δ compared to the original value
Sample 3: Yellowness Index of 10 Δ compared to the original valueYellowness Index measurement is performed
according to ASTM D1925 (1977) test.
7
Why Lexan Thermoclear Sheet?Mechanical Properties
8
Temperature of the glazing material will increase due to the absorption of
direct sunlight Temperature increase depends on:
• Amount of solar intensity of the sun
• Amount of solar absorption of the glazing material.
Solar absorption depends on:
• Light transmission
• Color
Transparent dark tinted colors (bronze, gray,) absorb much more solar energy
than clear and opal white colors. Heat build up of dark tinted glazing can be
considerable especially during intense sun radiation
Temperature increase of a thermoplastic glazing:
• Has a negative influence in impact performance
• Can result in a dramatic loss of strength and stiffness.
RTI = Relative Temperature Index
RTI is the maximum service temperature at which at least 50% of the
mechanical
properties as impact, strength and stiffness of a thermoplastic will remain
over a long period of time of 10 years
Why Lexan* Thermoclear* Sheet?Mechanical Properties vs. Temperature
Temperature Ratings UL746B
9
Why Lexan* Thermoclear* Sheet?Mechanical Properties vs. Temperature
Lexan Thermoclear sheet performance at
elevated temperature:
• Excellent retention of impact strength
• Excellent retention of stiffness
• Retains 85% of its room temperature flexural
modulus at 82°C
• Shows also good behavior over an extended period
• Outperforms PMMA and PVC
Flexural modulus in N/mm2 x100
10
Lexan Thermoclear sheet has outstanding impact performance over a wide
temperature range, - 40°C to +120°C, and also after prolonged outdoor
exposure.
As a roof glazing material Lexan Thermoclear® sheet is subject to
extremes of weather ; storms, hailstones, wind, snowfalls and ice
formation. Under these conditions, the product is virtually unbreakable
and is able to withstand the subsequent temperature change to sunny
conditions without breaking or buckling.
Why Lexan* Thermoclear* Sheet?Impact Strength
In a test developed by the Dutch Testing Institute TNO, samples of Lexan
Thermoclear sheet have been subjected to simulated hail-stones of
varying diameters without significant damage. A test sample is clamped
into a metal frame and polyamide balls of varying diameters are fired at
the surface of the sample using a pressurized air gun.
In practice, hail-stones with a diameter of 20 mm can reach a terminal
velocity of around 21 m/s. Under these conditions materials such as glass
and acrylic fail.
It should be noted that when the glass and the acrylic are tested their
failure characteristics are typically brittle, whilst the Lexan Thermoclear
showed ductile behavior: upon impact the ball will leave indentations
but the sheet will not break.
SABIC Innovative Plastics offers a Ten Years Written Limited Warranty
on Lexan Thermoclear sheet covering loss of strength or impact due to
weathering.
Hail Simulation Test Results:
11
Why Lexan* Thermoclear* Sheet?Light Transmission
Light TransmissionThe sunlight which reaches the surface of the earth has a
wavelength that ranges between 295 – 2140 nanometers
(10E-9 meters). This optical window is divided into the
following sections:
UV-B Middle ultraviolet region 280
– 315 nm
UV-A Near ultraviolet region 315
– 380 nm
Visible light region 380 – 780 nm
Near infra-red region 780 – 1400 nm
Middle infra-red region 1400 – 3000 nm
As shown in the graph left, Lexan Thermoclear sheet has the
highest transmission in the visible light.
12
Structure grade name
gauge
(mm)
weight
(kg/m2)
rib
distance
(mm)
ISO 10077
U value
(W/m2 K)
LT clear
112 (%)
LT opal white
WH7A092X
(%)
TST clear
112 (%)
TST opal white
WH7A092X
(%)
2-Wall Rectangular LT2UV452RS10 4.5 1.0 6 3.86 83 67 83 70
LT2UV62RS13 6 1.3 6 3.56 82 66 82 69
LT2UV82RS15 8 1.5 10 3.26 81 64 82 68
LT2UV102RS17 10 1.7 10 3.02 81 64 80 68
3-Wall Rectangular LT2UV163TS27 16 2.7 20 2.27 74 63 78 69
5-Wall Rectangular LT2UV105R175 10 1.8 8 2.39 65 60 65 59
5-Wall X-Structure LT2UV163X29 16 2.8 16 2.10 67 60 71 64
9-Wall X-Structure LT2UV169X 16 2.50 20 1.77 54 47 54 49
U-values based on SABIC-IP calculated values according ISO 10077 (EN 673)
LT (Light Transmission) and TST (Total Solar Transmission) measurements acc. ISO 9050 (EN 410) on 600mm * 600mm samples
TST (Total Solar Transmission) divided by 100 equals Solar Heat Gain Coefficient (SHGC) or g-value
Despite transmitting visible light very well, Lexan Thermoclear
sheet is almost opaque to radiation in the UV and far infra-red
region. This useful shielding property can prevent discoloration of
sensitive materials such as fabrics or other organic materials
placed under or behind Lexan Thermoclear sheet glazing in, for
example, a factory warehouse, museum or shopping center.
Why Lexan* Thermoclear* Sheet?Light Transmission
13
Why Lexan* Thermoclear* Sheet?UV-Protection
Lexan Thermoclear Plus sheet (LT2UV)
Lexan* Thermoclear* Plus sheet features as of 4.5mm thickness a unique 2 side proprietary surface treatment designed to protect the
sheet against the degrading effects of ultra-violet radiation in natural sunlight.
2 sides UV protected surfaces offers advantage in economical cutting the sheet in desired shapes and installation mistakes are
minimized since both sheet surfaces may be faced outwards.
Lexan Thermoclear absorbs
UV-A & UV-B
Solar radiation has harmful
effect upon polymeric materials
Initiates degradation by
causing superficial surface
crazing
These crazes become sites for
further erosion from water,
dust, chemicals, etc.
14
How do we measure the long-term effects of weathering on
glazing materials?
Settings ATLAS CI5000
Standard ISO11341
Lightsource Xenon
Power
Radiation 300-400nM 50W/m2 300-400nM 50W/m2
Black standard temp 65C
Chamber temperature 40C
%RH 70%
Cycle Constant light Constant light
Spray on /off 18minutes on /102 minutes off
filters inner CIRA , outer Sodalime inner CIRA , outer Sodalime
Yellowness Index was measured according both
ASTM D1925 and ISO E0313 and Light
Transmission according ASTM D1003.
800 hours accelerated weathering according
ISO11341 is equivalent to 1 year outdoor
Mid European climate.
Why Lexan* Thermoclear* Sheet?UV-Protection
15
10 Years
15 Years
Years
ΔΔΔΔ Yi = 2
ΔΔΔΔ Yi = 4
ΔΔΔΔ Yi = 10
Unpro
tect
ed S
hee
t
Co-Extr
uded S
heet
Lexan Thermoclear Plus SheetLexan Thermoclear SunXP Sheet
Why Lexan* Thermoclear* Sheet?UV-Protection
16
Structure grade name
gauge
(mm)
weight
(kg/m2)
rib
distance
(mm)
ISO 10077
U value
(W/m2 K)
2-Wall Rectangular LT2UV452RS10 4.5 1.0 6 3.86
LT2UV62RS13 6 1.3 6 3.56
LT2UV82RS15 8 1.5 10 3.26
LT2UV102RS17 10 1.7 10 3.02
3-Wall Rectangular LT2UV163TS27 16 2.7 20 2.27
5-Wall Rectangular LT2UV105R175 10 1.8 8 2.39
5-Wall X-Structure LT2UV163X29 16 2.8 16 2.10
9-Wall X-Structure LT2UV169X 16 2.50 20 1.77
U-values based on SABIC-IP calculated values according ISO 10077 (EN 673)
Why Lexan* Thermoclear* Sheet?Thermal Insulation
The multi-wall structure of Lexan Thermoclear sheet offers significant advantages where thermal insulation is a major
consideration. The hollow form provides excellent insulation characteristics with heat losses significantly lower than mono-wall
glazing materials. Heat loss is normally referred to as the U-value, which is the amount of energy transmitted through a material
per square meter of glazing area and per degree temperature difference. It is expressed in terms of W/m2 K.
Energy Loss CalculationsThe need to reduce energy consumption, and therefore energy costs, is one of the highest priorities in any business today. Substantial
savings of more than 50% are possible when installing Lexan Thermoclear sheet instead of mono-layer glass. When calculating
according to the guidelines given in the DIN standard 4701, an average annual saving of between 0.9 - 1.3 liters of oil or 1.0 - 1.5 m3
of gas per m2 of glazing area will be obtained by decreasing the U-value by 0.1 W/m2K.
17
Cold RadiationThe excellent insulation properties of Lexan Thermoclear sheet will also contribute to a reduction in the radiation of cold
into the building. The lower the U-value, the higher the inner sheet surface temperature will be maintained during the
winter season.
An example of the temperature profile through 6 mm Lexan
Thermoclear sheet when the outside temperature is -10°C and the
inside building temperature is +20°C.
Comparison Lexan Thermoclear sheet with single glazed glass under the
same conditions. The inside glass surface temperature is well below zero,
which means that cold radiation will negatively influence the overall
building temperature and will affect the comfort level near the windows.
Why Lexan* Thermoclear* Sheet?Thermal Insulation
18
Why Lexan* Thermoclear* Sheet?Solar Control IR
Current architectural design calls for building glazing's that permits high
levels of natural light, for both aesthetics and to reduce energy for interior
lighting. However, intensive use of glazing can lead to rapid interior heat
buildup due to penetration of near-infrared (IR) radiation (solar
transmission) through the glazing, especially in hot and sunny climates.
This, in turn, can raise energy costs for cooling the building.
Previous solar-control glazing, the only polymer alternative, used a
screen-printed coating or a coextruded layer on one side of the sheet to
absorb IR transmissions. But the coating and co-extruded layer made the
glazing translucent – at best – or opaque, greatly reducing light
transmission. Hence, architects who wanted to use polymer glazing had to
choose between light transparency and solar control. They could not find
both properties in one product unless they went to expensive solar
controlled glass.
Lexan Thermoclear Sheets have the highest transmission in the
visible part of the light.
Lexan Thermoclear Solar Control IR sheet selectively blocks the
near infrared region of the light, therefore reduces the heat build up.
19
Why Lexan* Thermoclear* Sheet?Dripgard
Lexan Thermoclear Dripgard Sheet
Guards the Light Transmission of Your
GreenhouseFeatures•A unique proprietary hydrophilic coating which reduces the
contact angle of condensation droplets
•Light transmission is not blocked by condensation droplets
•Helps prevent dripping of water droplets onto crops/plants in
your greenhouse
•1 side UV protection
•10 year written limited warranty
•Available in gauges 4.5-6-8-10-16mm, other gauges and
structures on request
How Does It Work?
Reduces the contact angle
droplets
Lexan Thermoclear Dripgard Sheet
20
Why Lexan* Thermoclear* Sheet?EasyClean
Enlarges the contact angle
droplets
droplets
Lexan Thermoclear Sheet
Lexan Thermoclear EasyClean Sheet
Features•A unique hydrophobic coating on the outside
surface that
• Reduces the surface tension of
polycarbonate and increases the
contact angle of water to the sheet.
• Causes larger droplets to form and
wash away dirt, leaving the multiwall
panels almost spotless for longer time.
•Reducing the frequency and the associated cost
of cleaning.
•All the benefits of having high clarity of Lexan
sheet
•2 side UV protection
Lexan Thermoclear EasyClean Sheet
Self- cleaning For Your GreenhouseHow Does It Work?
21
Why Lexan* Thermoclear* Sheet?Softlite
New Era in Light
Diffusion• High Light Transmission combined with 100% light
diffusion
• Excellent candidate for Greenhouses in area’s with a
high amount of sun hours/day
• Reduces the so called “arc” or “rainbow” effect on the
sheet with direct sunlight
• UV protection coating on both sides
• 10 year written limited warranty
• Available in gauges 4.5-6-8-10 and 16mm, other gauges
and structures on request
The new 8mm Lexan* Thermoclear* Softlite Sheet
offering up to 79% Light Transmission
22
